Electrosynthesis of Cyclic Isoureas and Ureas Through Contiguous Heterofunctionalizations.

An efficient synthetic protocol for the selenylated cyclic isoureas was developed using electrochemical activation of diselenides. This sustainable approach permitted transition metal and chemical oxidant-free difunctionalization of olefins and overall access to distinct 1,2,3 triheterofunctionalized carbon skeletons. Excellent functional group tolerance was noticed, allowing the synthesis of a series of cyclic isourea derivatives.

Electro-oxidative Synthesis of Unsymmetrical Alkyne-1,4-diones via Sequential Ring Formation and Cleavage.

Synthesis of unsymmetrical but-2-yne-1,4-diones is reported through oxidative alkyne translocation of readily accessible homopropargylic alcohols. The developed method consists of an unprecedented one-pot sequential electro-oxidative annulation-fragmentation-chemical selenoxide elimination process. Excellent functional group compatibility was observed, and an array of yne-1,4-diones were synthesized.

Electrochemical Organoselenium Catalysis for the Selective Activation of Alkynes: Easy Access to Carbonyl-pyrroles/oxazoles from -Propargyl Enamines/Amides.

Intramolecular electro-oxidative addition of enamines or amides to nonactivated alkynes was attained to access carbonyl-pyrroles or -oxazoles from -propargyl derivatives. Organoselenium was employed as the electrocatalyst, which played a crucial role as a π-Lewis acid and selectively activated the alkyne for the successful nucleophilic addition. The synthetic strategy permits a wide range of substrate scope up to 93% yield.